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finlep [7]
2 years ago
14

The horn on a fire truck sounds at a pitch of 350 hz a. what is the perceived frequency when the fire truck is moving toward you

at 20m/s? b. What is the perceived frequency when the fire truck is moving away from you at 20m/s: assume the speed of sound in air is 343m/s.
​
Physics
1 answer:
solong [7]2 years ago
5 0

The perceived frequency when the fire truck is moving toward you and away from you will be 370 Hz and 329.59 Hz respectively.

<h3>What is the Doppler effect?</h3>

A sudden change in the frequency due to the distance between the objects and source is explained by the doppler effect.

As the source and observer travel toward each other, the frequency of sound, light, or other waves increases or decreases.

The perceived frequency when the fire truck is moving toward you;

\rm r' = (\frac{v+v_0}{v}) V \\\\ \rm r' = (\frac{343+20}{343}) 350 \\\\ r' =370.4  \  Hz

The perceived frequency when the fire truck is moving away from you;

\rm r' = (\frac{v-v_0}{v}) V \\\\ \rm r' = (\frac{343-20}{343}) 343 \\\\ r' =329.59  \  Hz

Hence, the perceived frequency when the fire truck in cases 1 and 2 will be 370 Hz and 329.59 Hz.

To learn more about the doppler effect refer to the link;

brainly.com/question/15318474

#SPJ1

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To solve this exercise it is necessary to apply the concepts related to the Snells law.

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\theta_2 = Refracted angle

Our values are given by

n_1 = 1.550

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\theta_2 =90\° \rightarrowRefractory angle generated when light passes through the fiber.

Replacing we have,

(1.55)sin \theta_1 = (1.361) sin90

sin \theta_1 = \frac{(1.361) sin90}{(1.55)}

\theta_1 =sin^{-1} \frac{(1.361) sin90}{(1.55)}

\theta_1 =61.4\°

Now for the calculation of the maximum angle we will subtract the minimum value previously found at the angle of 90 degrees which is the maximum. Then,

\theta_{max} = 90-\theta \\\theta_{max} =90-61.4\\\theta_{max}=28.6\°

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Answer:

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